Overall I am very happy with the form and function of this unit. It is so much more capable and faster than my old 60CSx.

But I have had the unit shut down several times in the few days I have had it. Today I purposely got it to happen several times by doing the following:

Went to the map screen page and then >Find>Waypoint> then scrolled down to 2nd waypoint in the list, "Test2". Then >Menu>Select Symbol which goes to the screen with all available waypoint symbols to select. I did not select one, but just tried to use the quit button 3 times to go back to the map screen. About 3/4 of the time it exits back to the map screen as expected. But the other times, after the first quit, the 2nd or 3rd quit does not do anything. When I try that 3rd or 4th quit, the unit immediately powers off. It can be started﻿ right back up with the power button like nothing happened. But it would be annoying if I was out in the woods creating a track or whatever and this happened.

I have also had the unit not communicate with the computer several times when plugged in. Usually just need to disconnect and reconnect to get it to go. But a few times, it was frozen with a faded out "GARMIN" on the screen. Needed to remove and reinsert the batteries to get it to come back to life.

This next issue hopefully will go away once I start using rechargeable batteries, but the manual DOES say alkaline can be used. What happens is that after probably 2 or 3 hours on alkaline battery use, with the battery level indicator down one bar from full, a persistent message keeps popping up on the screen saying that the battery level is too low to properly run the backlight. The unit continues to work as it should, including the backlight, but the message keeps repeatedly popping up.

Finally, yesterday when the batteries did get very low, instead of just shutting off like my 11 year old 60CSx does, the 66 froze with that faded "GARMIN" on the display. Inserting fresh batteries allowed it to be powered back up. Interestingly with the batteries removed from the unit, the screen continued to display the faded "GARMIN".

We currently have several pages of known bugs with the initial release of the GPSMAP 66 (Firmware 2.10) and are hoping Garmin will resolve the majority of them before the next release.

I see some of them in this forum and two listed on the GPSMAP 66 "Known Issues" page. Is there a link to see all the several pages of know bugs you mention above? It would be nice to see them all in one place and to see if I can reproduce any myself.

If you look at the Common Issues pages for the Montana or Oregon 6x0 (for example), there are always quite a few when the devices are brand new. This is normal Garmin R&D. Congratulations, as a GPSMAP 66 owner, you're part of it!

I want to wait until the first new release, then I will start posting bugs that still exist. With an expected update any minute now, doing otherwise I feel would be very unproductive.

I changed to Spanner a few days ago and so far all is OK. I may change back just to see if the rare issue I had with freezing after unplugging the USB comes back or not. If it happens to not be a result of being in Garmin Serial mode, I may just keep it there. The thing is that in Spanner, when you plug it in, the unit powers on and then makes you choose whether you want to use the 66 plugged in or enter Mass Storage Mode. Since I never use the 66 plugged in and 100% of the time want Mass Storage Mode when connecting it, I would prefer just to plug it in and have it go to MSM.

I noticed another possible issue today, but need to look closer at the settings to make sure it is not a result of how I have something set. What happened is this: With Auto Pause on it stops recording as I have it set at, less than .25 mph. It also seems like it has to be at that speed for 20 or 30 seconds before it stops recording although I did not see a setting for that. But when it has stopped recording because I am at a standstill, when I begin to walk again, it is always takes between 25 and 40 feet of movement before it starts recording again. Then when I look at the track later it has connected the last point when I stopped to the first one it recorded when I began moving again. Usually this is not an issue if that straight connecting line is on a fairly straight trail. But one example where it does make a difference in the true track is this: If I stop 20 feet before a switchback, then start walking around and past the switchback before it starts recording again, the corner is really cut off. Not sure why it does not start recording as soon as I start moving again, but I don't see a setting that might control that?

Lets say you are having a great day and your GPSr is showing 8ft estimated location accuracy. That is radius. Diameter would be 16ft. Minimum. How far do you think you have to move before the GPSr can deduce, beyond shadow of doubt, that you are indeed moving again? Hint: The new estimated error circumference must be outside the original from the stopped position.

If you stop too close to a switchback, and you want to be sure it is on your track log, simply open the Recording Controls and manually restart the recording!